JP6909163B2 - Thermosetting polyester foam and its manufacturing method - Google Patents

Description

The present invention relates to a solid thermosetting foam obtained by a chemical reaction and foaming of an effervescent composition containing a polyol component, a polyhydric acid component, a surfactant and an esterification catalyst.

It is known that a thermosetting polyester foam is prepared by reacting a polyol with a polyhydric acid.

In WO 2010/05/9925, highly crosslinked polyesters are obtained in two steps: the first step is non-reaction by the reaction of the polyol with the polyhydric acid at a relatively low temperature. It consists of forming a cross-linked prepolymer; the second step is pre-in the presence of a cross-linking agent or polymerization (esteration) catalyst at either a second temperature higher than the first temperature or a moderate temperature. It consists of cross-linking the polymer. The absence of a catalyst in the first step appears to be essential for carrying out this step in two steps.

Certain cured polymers are listed as foams. However, their density is relatively high (Example 12: 350 kg / m ³ ; Example 16: 190 kg / m ³ ). The use of physical or chemical foaming agents is envisioned (see [0040]).

WO 2012/052385 is a foamed polymer obtained by reacting glycerol and citric acid at a temperature of 80-130 ° C., optionally in the presence of an esterification catalyst, until the conversion is at least 90%. Is described. The reaction mixture is heated at a higher temperature, close to 150 ° C., when a conversion of at least 90%, preferably 98% is achieved. The first step at low temperatures is intended to avoid decarboxylation of citric acid as much as possible.

The methods described in this document require very long reaction times of hours to tens of hours. The polymerization is preferably carried out in a non-adhesive mold made of, for example, Teflon. The foam thus obtained has a density of 200-850 g / liter.

WO 2013/121033 describes an improvement in this method, where the polymerization of glycerol and citric acid is in contact with a substrate having an outer layer containing at least a metal, metal oxide or metal halide. Will be done. This method provides a foam with a more regular pore size than that prepared by the method described in WO 2012/052385. The density according to this claim is 50 to 850 g / liter. The foam prepared in the examples has a density of 282 g / liter to 482 g / liter.

The present invention is known for foaming in a single polymerization step performed at high temperature and within a limited time by using an esterification catalyst and a surfactant in the first reaction mixture containing glycerol and citric acid. It is based on the discovery that excellent quality foams, which are less dense than the body and have fine and uniform porosity, are obtained.

In the methods of the invention, we do not seek to avoid the decomposition of _{aconitic acid and citric acid, which gives CO 2.} On the contrary, in order to use citric acid as a chemical pore-forming agent (chemical foaming agent, chemical foam-forming agent) that does not require the addition of a physical pore-forming agent, the reaction medium is rapidly heated at a high temperature. ..

Therefore, one subject of the present invention is a method for producing a thermosetting polyester foam, which comprises the following sequential steps:
(A) To provide an effervescent and thermosetting composition, wherein the composition comprises a polyol component comprising at least one element selected from −glycerol, diglycerol and glycerol oligomers.
-Polyvalent acid components, including citric acid,
-Surfactants and
-Esterification catalyst,
Contains;
(B) Introducing the effervescent and thermosetting composition into a mold or applying the effervescent composition to a support;
(C) The effervescent and thermosetting composition at a temperature of at least 135 ° C., preferably at least 150 ° C., and even more preferably at least 175 ° C. for reacting the polyol component with the polyhydric acid component. Heating an object to form a block of thermosetting polyester foam.

Another subject of the present invention is
-A polyol component containing at least one element selected from glycerol, diglycerides and glycerol oligomers.
-Polyvalent acid components, including citric acid,
-Surfactants and
-Esterification catalyst,
Is used as an effervescent and thermosetting composition for the production of foam-type insulating products.

Therefore, the effervescent and thermosetting composition contains four essential components: a polyol component, a polyhydric acid component, a surfactant and an esterification catalyst.

The polyhydric acid component can contain a polyhydric acid other than citric acid, and the polyol component can include a polyol other than glycerol, diglycerol and a glycerol oligomer, a so-called polyhydroxylated compound. Examples of other polyhydric acids and polyols are shown below.

As used herein, the amount or content of a polyol or polyhydric acid component is always understood to mean for all polyols or all polyhydric acids present in the composition.

This definition of polyols and polyhydric acid components does not preclude the possibility that certain surfactants may be included in the polyol or polyhydric acid components. This is the case, for example, with alkyl polyglycosides (APGs) contained in preferred surfactants. Alkyl polyglycosides contain one or more sugar units (polyhydroxylation units), which also act as a surfactant by adjusting and controlling the porosity of the resulting foam, and are polyvalent acids. It also acts as a polyol that can participate in the formation of a cured three-dimensional network by the reaction of the components with the acid groups.

In the present invention, the compound present in the effervescent and thermosetting composition is also the first component of the four essential components of the composition, and the four essential components (polyol component, polyhydric acid component). , Surfactants, esterification catalysts), when it can also be considered to be, it will be considered to be both one and the other. It means that the amount of each of these two components is taken into account.

in this way,
48% by weight glycerol,
47% by weight citric acid,
3% by weight alkyl polyglycosides and
The effervescent and thermosetting composition containing 2% by weight of the esterification catalyst has a polyol component content equal to 51% (48% glycerol + 3% alkyl polyglycoside) and a polyhydric acid component content of 47%. The surfactant content would be equal to 3%, and the esterification catalyst content would be equal to 2%. Since the 3% alkyl polyglycosides are counted twice, the numerical sum of these four components is of course greater than 100%.

(A R-PO ₄ H _2, where, R is an aliphatic chain) specific alkylphosphonic acid, a component that can dual role of the role and the role of an esterification catalyst of a surfactant Configure another example.

The first essential component of the effervescent composition is a polyol component. This component comprises at least one element selected from the group consisting of glycerol, diglycerol and oligoglycerol. Compounds of the following formula:
(1) HO (CH _2- CHOH-CH _2- O) _n- H
(In the above equation, n is an integer of 3 to 6)
And the aliphatic monoether or polyether of the compound of formula (1) in which up to 30% of the -OH functional groups may be etherified with an aliphatic alcohol is considered to be an oligoglycerol.

The polyol component preferably contains at least 15% by weight, preferably at least 20% by weight, particularly at least 25% by weight, based on the total dry weight of the polyol component. We have actually observed that large amounts of glycerol monomers make it possible to obtain low density, uniform stomatal foams.

The polyol component is preferably no glycerol, not diglycerol, and no glycerol, preferably up to 30% by weight, especially up to 20% by weight, ideally up to 10% by weight, based on the total dry weight of the polyol component. Contains polyols that are also non-oligomers.

These polyols are preferably bio-based polyols, especially sugars and sugar alcohols (hydrogenated sugars).

The sugar that can be used as part of the polyol component can be a reducing sugar or a non-reducing sugar.

The term "reducing sugar" is understood to mean a carbohydrate of _{formula C n} (H ₂ O) _p having at least one aldehyde or ketone group (reducing group). Reducing sugars that can be used in the present invention include monosaccharides and polysaccharides (appropriate disaccharides, oligosaccharides and polysaccharides).

Examples of monosaccharides include monosaccharides containing 3 to 8 carbon atoms, preferably aldoses, preferably aldoses containing 5 to 7 carbon atoms. Particularly preferred aldoses are natural aldoses (belonging to the D series), especially hexoses such as glucose, mannose and galactose.

Lactose or maltose is an example of a disaccharide that can be used as a reducing sugar.

Starch hydrolysates obtained by enzymatic or acid hydrolysis of starch can also be used advantageously.

Non-reducing sugars that can be used are saccharose and trehalose.

Examples of hydrogenated sugars include hydrogenated products of erythritol, arabitol, xylitol, sorbitol, mannitol, iditol, maltitol, isomartitol, lactitol, cellobitol, palatinitol, maltotriitol and starch hydrolysates. can.

The second essential component of the effervescent composition is the polyhydric acid component. The polyhydric acid component preferably contains at least 50% by weight, particularly at least 65% by weight, ideally at least 80% by weight of citric acid, based on the total weight of the polyvalent acid component.

There may be other polyhydric acids that can react with the polyol component to form a polyester network. These other polyhydric acids are preferably polyhydric acid monomers, i.e. polyhydric acids that are not formed by polymerization of monomeric units having acid groups such as poly (acrylic acid).

Other polyvalent acids are preferably polycarboxylic acids such as dicarboxylic acids, tricarboxylic acids or tetracarboxylic acids.

Dicarboxylic acids include, for example, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimeric acid, suberic acid, azelaic acid, sebacic acid, malic acid, tartaric acid, tartron acid, aspartic acid, glutamic acid, fumaric acid, itacon. Acids, maleic acid, traumatic acid, succinoic acid, phthalic acid and derivatives thereof, especially those containing at least one boron or chlorine atom, tetrahydrophthalic acid and derivatives thereof, especially those containing at least one chlorine atom, such as chlorend. Includes acids, isophthalic acids, terephthalic acids, mesaconic acids and citraconic acids.

Tricarboxylic acids include, for example, tricarbaryl acid, 1,2,4-butanetricarboxylic acid, aconitic acid, hemimeric acid, trimeritic acid and trimesic acid.

Examples of the tetracarboxylic acid include 1,2,3,4-butanetetracarboxylic acid and pyromellitic acid.

The polyol and polyacid components defined above together are at least 60%, preferably at least 70%, particularly at least 80% of the dry weight of the effervescent and thermosetting composition.

The polyol component is preferably 15 to 60% by weight, particularly 20 to 50% by weight, ideally 25 to 45% by weight, based on the total weight of the polyol component and the polyhydric acid component. Thus, theoretically, the polyvalent acid component is preferably 40-85% by weight, particularly 50-80% by weight, ideally 55-75% by weight of the total weight of the polyol component and the polyvalent acid component. It is understood that there is.

In known methods, the respective amounts of the polyol component and the polyvalent acid component are 0.65 to 1.5 for -OH and COOH functional groups, preferably 0.8 to 1.4, especially 1.0 to. It will be adjusted to be present in a molar ratio of 1.3.

The third essential component of the effervescent and thermosetting composition is a surfactant. In this application, the term also includes a mixture of several surfactants.

The role of this component is to improve the quality of the foam, i.e. to reduce the pore size to narrow the pore size distribution and reduce the density of the resulting cured foam.

Surfactants preferably have a hydrophilic-lipophilic balance (HLB) of 3 to 13, preferably 5 to 8.

In one embodiment, the surfactant is a mixture of anionic surfactant and cationic surfactant. In the field of liquid aqueous foams, the combination of two types of surfactants with opposite charges makes the surfactant film at the water / air interface by reducing the repulsive force between molecules with the same charge. It is known that it can be stabilized. As shown below in the examples, we have obtained excellent results with a mixture of sodium dodecyl sulfate (SDS) and tetradecyltrimethylammonium bromide (TTAB), and therefore a combination of these two surfactants. Use constitutes a preferred embodiment. The TTAB / SDS weight ratio is preferably 1.5 to 2.5, particularly 1.8 to 2.2, ideally close to 2.

Nonionic surfactants constitute an interesting alternative to the combination of anionic and cationic surfactants. In fact, in the case of nonionic surfactants, there is no repulsive force between hydrophilic heads with the same charge, and therefore certain nonionic surfactants are particularly suitable for the formation of good quality foams. ing. The nonionic surfactant used in the present invention preferably has an HLB of 3-13.

This is the case, for example, with alkyl polyglycosides (APGs), which are molecules containing hydrophilic heads formed from one or more sugar units grafted with alkyl fat chains.

The alkyl polyglycoside preferably contains 1 to 2 glucoside units, the alkyl chain preferably contains 8 to 14 carbon atoms, and is preferably a straight chain alkyl chain.

Products of the Glucopon brand, especially the Glucopon 600 CSUP (lauryl glucoside) and Glucopon 650 EC (cocoglucoside), can be cited as examples of alkyl polyglycosides.

The amount of surfactant is advantageously 0.1% to 10%, preferably 1% to 8%, particularly 2% to 6% of the total dry weight of the effervescent composition.

The fourth essential component of the effervescent and thermosetting composition used in the method of the present invention is an esterification catalyst. This catalyst is not necessarily essential, but is preferably a phosphorus-containing compound. Examples of preferable phosphorus-based catalysts include hypophosphite alkali metal salt (H ₂ PO ₂ M), phosphite alkali metal salt (HPO ₃ M ₂ ), polyphosphate alkali metal salt (M ₃ PO ₄ ), and phosphoric acid. Examples include catalysts selected from the group consisting of hydrogen alkali metal salts (M ₂ HPO ₄ ), phosphoric acid (H ₃ PO ₄ ), alkylphosphonic acid (RPO ₃ H ₂ ) and mixtures of two or more of these compounds. can. Alkali metal hypophosphates are particularly preferred.

The concentration of the esterification catalyst is typically 0.1% to 10% by weight, preferably 1% to 8% by weight, particularly 2% to 6% by weight, based on the dry weight of the effervescent composition. %.

The mixture of the four essential ingredients described above is advantageously a solution. It may be useful to add a certain amount of water to dissolve all the ingredients. Water can also help dilute the composition to facilitate fluidization or application during step (b) of the method of the invention. However, it will generally be required to limit the amount of water in the effervescent composition, as the esterification reaction is initiated only after the complete evaporation of water and the evaporation of water has an undesired energy cost. ..

Thus, the effervescent composition is up to 60% by weight, preferably up to 25% by weight, more preferably up to 15% by weight, especially up to 5% by weight, based on the total weight of the effervescent composition. Will contain water.

The effervescent composition used in the present invention is also one or more inorganic fillers of 30% by weight or less, preferably 20% by weight or less, particularly 10% by weight or less, based on the dry weight of the total effervescent composition. Organic fillers can be included.

Finally, effervescent compositions are conventionally used in the art for the processing and modification of polymers such as dyes, pigments, antibacterial or antifungal agents, flame retardants, UV absorbers or hydrophobic agents1 Other additives than seeds can be included. In total, these additives are up to 10% of the dry weight of the composition.

It is important to note that the effervescent composition can, in principle, contain an organic foaming agent such as pentane, but is not necessarily added.

This is because citric acid present in the polyhydric acid component acts as a foaming agent. When the effervescent composition is heated in step (c) at a temperature close to 175 ° C., citric acid decomposes in a known manner to produce aconitic acid and CO ₂ (MM Barbooti et al., “Thermal Decomposition of Citric Acid). ", Thermochimica Acta, 98 (1986), 119-126; D. Wyrzykowski et al.," Thermal Behavior of Citric Acid and Isomeric Aconitic Acids ", J. Therm. Anal. Calorim. (2001), 104: 731-735). It is illustrated below in an exemplary embodiment that good quality and low density foams can be obtained in the absence of a physical foaming agent. The addition of the organic foaming agent is therefore superfluous when step (c) is performed at a temperature above 170 ° C. In one preferred embodiment of the method of the invention, the effervescent composition is therefore essentially free of organic physical effervescent agents.

When the effervescent composition is applied on the support in the form of a continuous film, the thickness of the film before heating, i.e. before effervescence and curing, is advantageously equal to at least 1 mm, preferably at least 2 mm. Especially equal to at least 5 mm and more preferably equal to at least 10 mm.

The volume of foam blocks formed can vary over a very wide range. The effervescent composition is potentially infinite when used, for example, in a continuous process of forming strips or profile elements of insulating material. When using the effervescent composition to form separate blocks, such as slabs or sheets of foam, the amount is preferably equal ^{to at least 500 cm 3 in volume of each block of thermosetting solid foam.} at least equal to 0.001 m ^3, is an amount such as in particular at least equal to 0.01 m ^3.

The foam block is preferably in the form of a slab.

In principle, it is known in the field of polymer processing and modification, such as hot air, heat radiation, microwaves, or contact with a thermal support (mold), to heat the effervescent composition in step (c). Standard means can be used.

Of course, the temperature of the heating means (drying furnace, support, mold) may be higher than the above reaction temperature, for example, 160 to 210 ° C.

The duration of the heating step (step (c)) depends not only on the temperature, but also on the heating means and the volume / surface ratio of the blocks of foam formed. The duration is generally 10 minutes to 5 hours, preferably 20 minutes to 4 hours, especially 30 minutes to 3 hours.

Another subject of the invention is a solid polyester foam that can be obtained by the method that is the subject of the invention.

In the absence of dyes, the solid foam prepared by the methods of the invention is generally light in color, typically ivory, yellow or beige. Their density is 20-80 kg / m ³ , preferably 25-50 kg / m ³ , especially 27-48 kg / m ³ .

The foam has closed cells with an average pore diameter of 100-800 μm, as determined by X-ray tomography.

Several effervescent and thermosetting compositions are prepared by adding powdered citric acid to an aqueous solution containing glycerol, diglycerol, oligoglycerol or a mixture thereof. Then, an esterification catalyst in powder form (sodium hypophosphate monohydrate) and then a surfactant are added to adjust the solid content of the mixture to 66% by weight. The mixture is stirred at ambient temperature until the citric acid powder dissolves. Table 1 shows the amount of each of the components used as a dry substance and shows the total solid content of the obtained composition.

The reactive solution is then poured into a rectangular mold, the bottom of which is covered with a sheet of aluminum. The thickness of the liquid film is about 1 mm. Heat the mold in an aeration drying oven whose temperature has been adjusted to 180 ° C for 3 hours.

After removing the mold from the drying oven and cooling the formed foam to ambient temperature, the thickness of the formed foam is evaluated using the following rating scale:

-: Less than 0.5 cm
+: 0.5-1 cm
++: 1.1 ~ 2 cm
+++: 2.1 ~ 3 cm
++++: 3.1-4 cm
+++++: Over 4 cm

*次亜リン酸ナトリウム水和物
**テトラデシルトリメチルアンモニウムブロミド（TTAB）及びドデシル硫酸ナトリウム（SDS）を、水中25％溶液の形態で添加したもの。TTAB/SDS重量比=2
***約3分の1で各成分を含む混合物
****ポリグリセロール-4（CAS番号25618-55-7）は、約2％のジグリセロール、43％のトリグリセロール、34％のテトラグリセロール、14％のペンタグリセロール、6％のヘキサグリセロールを含む。

* Sodium hypophosphate hydrate
** Tetradecyltrimethylammonium bromide (TTAB) and sodium dodecyl sulfate (SDS) added in the form of a 25% solution in water. TTAB / SDS weight ratio = 2
*** Mixture containing each ingredient in about one-third
**** Polyglycerol-4 (CAS No. 25618-55-7) contains approximately 2% diglycerol, 43% triglycerol, 34% tetraglycerol, 14% pentaglycerol, and 6% hexaglycerol. include.

All the obtained foams have a fine and uniform porous structure. The foam is ivory or beige. 1 and 2 show slabs and blocks of the resulting foam, respectively, as an example. In these tests, the esterification catalyst (sodium hypophosphate) and a surfactant (combination of cationic and anionic surfactants) can be used in combination to obtain a foam in a single high temperature step. It shows that there is.

Tests using polyglycerol-4 as the polyol component are believed to show that foaming is inhibited by the absence of glycerol monomers and the substantial absence of dimers. The presence of certain amounts of glycerol monomer and / or dimer is believed to be important for foaming.

Alkyl polyglycosides (neutral surfactants) give results comparable to the TTAB / SDS combination.

We tested with an anionic surfactant (Disponil ™ SUS 87 Spez; disodium salt of ethoxylated decyl alcohol ester), which was used in the absence of a cationic surfactant. Surfactants do not make it possible to obtain foam.

Even if a nonionic surfactant having an HLB of 14 (Disponil ™ PGE 110; polyglycol diether of an aliphatic diol) is used, no foam is obtained.

Partial Substitution of Glycerol with Other Polyols Table 2 below shows the results obtained from tests performed under the same conditions as Table 1. About one-third of glycerol / diglycerol / oligoglycerol was replaced with different polyols (hydrophobic starch, trimethylolpropane, pentaerythritol).

*次亜リン酸ナトリウム水和物
**テトラデシルトリメチルアンモニウムブロミド（TTAB）及びドデシル硫酸ナトリウム（SDS）を水中25％溶液の形態で添加したもの。TTAB/SDS重量比=2

* Sodium hypophosphate hydrate
** Tetradecyltrimethylammonium bromide (TTAB) and sodium dodecyl sulfate (SDS) added in the form of a 25% solution in water. TTAB / SDS weight ratio = 2

It can be observed that this partial substitution of glycerol or oligomers thereof never impairs the quality of the foam formed.

<< Total replacement of glycerol with other polyols >>
Table 3 below shows the results obtained by the tests performed under the same conditions as in Table 1, except that all of the glycerol / diglycerols / oligoglycerols were replaced with different polyols (hydrophobic starch, maltitol, isosorbide).

*次亜リン酸ナトリウム水和物
**テトラデシルトリメチルアンモニウムブロミド（TTAB）及びドデシル硫酸ナトリウム（SDS）を水中25％溶液の形態で添加したもの。TTAB/SDS重量比=2
*** 疎水性変性デンプン

* Sodium hypophosphate hydrate
** Tetradecyltrimethylammonium bromide (TTAB) and sodium dodecyl sulfate (SDS) added in the form of a 25% solution in water. TTAB / SDS weight ratio = 2
*** Hydrophobic modified starch

It is observed that total substitution of glycerol or oligomers thereof interferes with the formation of foam. Therefore, the presence of glycerol, diglycerol or oligoglycerol proves to be essential for foam formation.

<< Substitution of part or all of citric acid with another polyhydric acid >>
Table 4 below shows the results obtained from tests performed under the same conditions as Table 1, except that some or all of the citric acid was replaced with another polyhydric acid.

*次亜リン酸ナトリウム
**テトラデシルトリメチルアンモニウムブロミド（TTAB）及びドデシル硫酸ナトリウム（SDS）を水中25％溶液の形態で添加したもの。TTAB/SDS重量比=2
***(C₈-C₁₄)アルキルポリグリコシド(Glucopon 650 EC)を52重量％の固形分を有する水溶液の形態で添加したもの

* Sodium hypophosphate
** Tetradecyltrimethylammonium bromide (TTAB) and sodium dodecyl sulfate (SDS) added in the form of a 25% solution in water. TTAB / SDS weight ratio = 2
*** (C _8- C ₁₄ ) alkyl polyglycoside (Glucopon 650 EC) added in the form of an aqueous solution with a solid content of 52% by weight

It is observed that total substitution of citric acid with other polyvalent acids interferes with the formation of foam. Partial substitution of citric acid does not impair the quality of the foam.

《Esterification catalyst》
When the test was conducted under the same conditions as in Table 1 except that sodium hypophosphate was removed, the formation of foam was greatly suppressed.

*テトラデシルトリメチルアンモニウムブロミド（TTAB）及びドデシル硫酸ナトリウム（SDS）を水中25％溶液の形態で添加したもの。TTAB/SDS重量比=2

* Tetradecyltrimethylammonium bromide (TTAB) and sodium dodecyl sulfate (SDS) added in the form of a 25% solution in water. TTAB / SDS weight ratio = 2

In the thermal weight analysis (TGA) test of an aqueous solution of citric acid containing sodium hypophosphite, sodium hypophosphate catalyzed the decomposition of citric acid as compared with the same solution containing no sodium hypophosphite. It has been shown to produce aconitic acid and CO _2.
The following aspects can be mentioned as aspects of the present invention:
<< Aspect 1 >>
A method for producing a thermosetting polyester foam, which comprises the following sequential steps:
(A) To provide an effervescent and thermosetting composition, wherein the composition comprises:
-A polyol component containing at least one element selected from glycerol, diglycerides and glycerol oligomers.
-Polyvalent acid components, including citric acid,
-Alkyl polyglycosides, and surfactants selected from mixtures of anionic surfactants and cationic surfactants, and
-Esterification catalyst.
(B) Introducing the effervescent and thermosetting composition into a mold, or applying the effervescent composition to a support.
(C) The effervescent and thermosetting composition is heated at a temperature of at least 135 ° C., preferably at least 150 ° C., and the polyol component is reacted with the polyhydric acid component to obtain a thermosetting polyester foam. Forming blocks.
<< Aspect 2 >>
The polyol component and the polyhydric acid component, in total, correspond to at least 60%, preferably at least 70%, particularly at least 80% of the dry weight of the effervescent and thermosetting composition. , The method according to aspect 1.
<< Aspect 3 >>
The method according to aspect 1 or 2, wherein the polyol component contains at least 15% by weight, preferably at least 20% by weight, particularly at least 25% by weight of glycerol.
<< Aspect 4 >>
The method according to any one of aspects 1 to 3, wherein the polyvalent acid component contains at least 50% by weight, preferably at least 65% by weight, particularly at least 80% by weight of citric acid.
<< Aspect 5 >>
The method according to any one of aspects 1 to 4, wherein the surfactant is a mixture of sodium dodecyl sulfate (SDS) and tetradecyltrimethylammonium bromide (TTAB).
<< Aspect 6 >>
The method according to any one of aspects 1 to 5, wherein the surfactant has a hydrophilic-lipophilic balance (HLB) of 3 to 13.
<< Aspect 7 >>
The polyol component is characterized by being 15% by weight to 60% by weight, preferably 20% by weight to 50% by weight, particularly 25% by weight to 45% by weight, based on the total weight of the polyol component and the polyhydric acid component. The method according to any one of aspects 1 to 6.
<< Aspect 8 >>
The effervescent composition comprises up to 60% by weight, preferably up to 25% by weight, preferably up to 15% by weight, particularly up to 5% by weight, embodiments 1-7. The method according to any one of the above.
<< Aspect 9 >>
The esterification catalyst is selected from phosphorus-containing compounds, preferably hypophosphorous acid alkali metal salt, phosphite alkali metal salt, polyphosphate alkali metal salt, hydrogen phosphate alkali metal salt, phosphoric acid, alkylphosphonic acid and The method according to any one of aspects 1 to 8, which is selected from the group consisting of a mixture of two or more of these compounds, and is particularly a hypophosphorous acid alkali metal salt.
<< Aspect 10 >>
The effervescent composition also contains one or more inorganic fillers or organic fillers of 30% by weight or less, preferably 20% by weight or less, particularly 10% by weight or less, based on the dry weight of all effervescent compositions. The method according to any one of aspects 1 to 9, characterized in that.
<< Aspect 11 >>
A polyester foam obtained by the method according to any one of aspects 1 to 10.
<< Aspect 12 >>
The polyester foam according to aspect 11, wherein the density is 20 to 80 kg / m3, preferably 25 to 50 kg / m3, particularly 27 to 48 kg / m3.
<< Aspect 13 >>
The polyester foam according to aspect 11 or 12, characterized in that it has closed cells.
<< Aspect 14 >>
The solid foam according to any one of aspects 11 to 13, wherein the average diameter of the pores determined by X-ray tomography is 100 to 800 μm.
<< Aspect 15 >>
Use of compositions containing the following as effervescent and thermosetting compositions for the manufacture of foam-type insulating products:
-A polyol component containing at least one element selected from glycerol, diglycerides and glycerol oligomers.
-Polyvalent acid components, including citric acid,
-Alkyl polyglycosides, and surfactants selected from mixtures of anionic surfactants and cationic surfactants, and
-Esterification catalyst.

Claims (9)

A method for producing a thermosetting polyester foam in a single polymerization step, which comprises the following sequential steps:
(A) To provide an effervescent and thermosetting composition, wherein the composition comprises:
-Polyol component, containing at least 15% by weight glycerol,
-A polyhydric acid component, containing at least 50% by weight citric acid,
-A surfactant selected from a mixture of an alkyl polyglycoside and an anionic surfactant and a cationic surfactant, and-an esterification catalyst which is sodium hypophosphite .
(B) Introducing the effervescent and thermosetting composition into a mold, or applying the effervescent composition to a support.
(C) The foamable and thermosetting composition is heated at a temperature of more than 170 ° C. , and the polyol component is reacted with the polyhydric acid component to form a block of a thermosetting polyester foam. The method according to claim 1, wherein the polyol component and the polyhydric acid component together correspond to at least 60% of the dry weight of the effervescent and thermosetting composition. The method according to claim 1 or 2 , wherein the polyvalent acid component contains at least 65 % by weight of citric acid. The method according to any one of claims 1 to 3 , wherein the surfactant is a mixture of sodium dodecyl sulfate (SDS) and tetradecyltrimethylammonium bromide (TTAB). The method according to any one of claims 1 to 4 , wherein the surfactant has a hydrophilic-lipophilic balance (HLB) of 3 to 13. The method according to any one of claims 1 to 5 , wherein the polyol component is 15% by weight to 60% by weight of the total weight of the polyol component and the polyhydric acid component. The method according to any one of claims 1 to 6 , wherein the effervescent composition contains up to 60% by weight of water. Any of claims 1 to 7 , wherein the effervescent composition also contains at least 30% by weight of one or more inorganic fillers or organic fillers based on the dry weight of all effervescent compositions. The method described in paragraph 1. The method according to any one of claims 1 to 8 , wherein the polyester foam has a density of 20 to 80 kg / m ^3.

Images